Engineered floor boards composed of laminated wood material layers are known whereby to provide an aesthetically pleasing appearance floor board at reduce cost due to the high cost of quality hardwood, such as maple wood, oak and walnut, to mention a few. When laminating or bonding different types of wood products together to create engineered floor boards various problems come into play has these different products react differently to changing climatic conditions particularly when subjected to humidity and loads subjecting the board to flexion and torsion. Another problem with these engineered floor boards is the telegraphy reflected in the top surface of the top layer which is a thin layer of quality wood and that problem has been addressed in our Canadian Patent No. 2,643,180 and entitled “Composite Engineered Wood Material Piece”, ranted on May 5, 2008. Reference is also made to US Patent Publication 2005/0268571, published on Dec. 8, 2005, which relates to a three layer hardwood floor board having a non-hardwood material middle layer which may be made from HDF or MDF boards.
Due to the rising cost of quality wood, the flooring manufactures strive to fabricate quality engineered wood floors at the lowest possible costs while considering the quality aspect of the product. Due to the high cost of the top wood layer of such floor board products, the thickness of the top wood layer is reduced and laminated to one or more substrate of lower quality and cost while trying to achieve a finished product having an ideal thickness, usually in the order of about ¾ inch (19 mm). The use of a low quality wood products such as oriented strand board (OSB) as a thick substrate wood result in an ideal solution to reduce costs. However, that product has certain disadvantages if bonded to a thin quality wood layer due to its composition of irregular compressed wood strands and flakes. Also, OSB tends to swell under local humid conditions and irregularities in its surface bonded to the thin top layer cause distortion and reflect or telegraph into the thin top layer causing an unpleasing appearance and distortion.
The use of an OSB layer as a substrate also has further problems to be resolved, such as the variable density thereof which poses the risk of the product delaminating when subjected to certain climatic conditions. The thicker is the top layer, the higher is the risk of fracturing the substrate and delaminating. Still further, because the OSB is formed or irregular wood strands and flakes lying unevenly across each other and mixed with adhesive and then pressed together, the outer surface of such wood boards is irregular and not perfect which would make it difficult to glue to the flat undersurface of the top layer and achieve a perfect bond between the thin top wood layer and the top surface of the OSB.
It would be desirable to use OSB as a substrate to fabricate a composite wood material piece to form floor boards or sheets including such product and overcome the above mentioned disadvantages of the OSB.